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31.
Acute phase proteins such as serum amyloid A, haptoglobin, and alpha 1-acid glycoprotein have been identified as markers of inflammation in cattle because they are produced by the liver in response to pro-inflammatory cytokines. This study was designed to assess whether they could be used to discriminate between acute and chronic inflammation. Their concentrations were measured in serum samples from 81 cattle in which inflammation was classified by thorough clinical examination, supported by postmortem findings, as being acute in severity in 31 and chronic in 50. The classical haematological markers of inflammation were also determined in blood from the animals. Serum amyloid A had a maximum (100 per cent) clinical sensitivity in discriminating between the acute and chronic cases, and haptoglobin had the highest clinical specificity of 76 per cent; counts of neutrophils and band neutrophils had sensitivities of 71 per cent and 42 per cent and specificities of 30 per cent and 72 per cent, respectively. It was concluded that serum amyloid A and haptoglobin may be used to discriminate between acute and chronic inflammatory conditions.  相似文献   
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The effects of feeding different levels of forages and concentrate, in a discontinuous feeding pattern, on the efficiency of feed utilisation and rumen function were studied using rumen fistulated sheep. Experiment 1 was a 4 × 4 latin square design to determine the whole tract digestibility and rumen characteristics of diets comprising 15% (C15), 25% (C25), 35% (C35) and 45% (C45) concentrate (energy-dense dairy pellets) with the rest of the diet being a combination of fresh short rotation ryegrass (Lolium mutiforum) and conserved (lucerne hay and maize silage) forages. In Experiment 2, the rumen degradation characteristics of feed ingredients were determined using the nylon bag technique. Daily dry matter intake (either expressed as g/kg LW or g/kg W 0.75) was 10% lower (p = 0.03) for the C15 diet compared with C25, C35 and C45 diets. The apparent in vivo digestibility of dry matter (DM) for C15 diet was 4% higher (p = 0.04) than the C35 and C45 diets which may be attributed to the high quality of the forage (ryegrass) used.Fibre digestibility decreased as proportion of concentrate in the diet increased. However, this was unlikely due to changes in the rumen fermentation pattern, as neither pH (6.1 ± 0.23) nor ammonia concentration (24.4 ± 6 mg/dl), were different (p > 0.05) among diets. Instead, the lower fibre digestion was most likely the result of different type and proportion of fibre among diets, as total rumen degradability and rate of fibre degradation in the rumen were higher (p = 0.001) for ryegrass than for other feedstuffs. There was no significant difference in total nitrogen balance and urinary allantoin excretion among diets, which indicated similar total microbial protein synthesis (MPS). The asynchrony observed, for N and energy availability in the rumen for different diets using Sinclair et al. [Sinclair, L.A., Garnsworthy, P.C., Newbold, J.R., Buttery, P.J., 1993. Effect of synchronizing the rate of dietary energy and nitrogen release on rumen fermentation and microbial protein synthesis in sheep. J. Agric. Sci. 120, 251–263] equation, was due to the feeding pattern used in this study leading to excess of N in relation to total organic matter digested in the rumen. In conclusion, feeding concentrates in the diets as PMR with conserved forages in a discontinuous feeding pattern may be valuable to develop feeding strategies in a pasture based system for high producing dairy cows without affecting the rumen system.  相似文献   
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A natural hybrid of Vipera ammodytes × Vipera berus was presented having low body weight, seizures and generalized swelling of the cephalic region. Based on the history of the case and clinical examination, hemorrhagic stomatitis of traumatic origin was diagnosed. The snake was kept in a terrarium with wood chips as a substrate, and the material had induced trauma in the oral mucosa which was further complicated with Salmonella Arizonae and Morganella morganii co-infection, abscessation and osteomyelitis. To the best of the authors’ knowledge, this is the first reported case of bacterial infection in European snake hybrids and one of a few case reports in European snakes. Although wood chips are an inexpensive substrate, based on our findings, they should be avoided when keeping and breeding European vipers.  相似文献   
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双链DNA(dsDNA)定量分析是植物分子生物学研究的基础,对基因型分析尤为重要。本研究以λ噬菌体dsDNA为标准样品,建立了荧光定量标准曲线,探讨荧光核酸定量通量性及其与紫外法定量的差异,并分析荧光染料在基因分型中的应用。结果表明,荧光染料能够对dsDNA进行高效微量定量分析(1.1ngmL-1),但因鉴定核酸的浓度较低,对小麦籽粒和叶片全基因组DNA定量时稀释倍数较大,易增大浓度误差。降低反应体系量导致标准曲线决定系数降低,影响测量准确性。精确定量dsDNA浓度时,总反应体系应大于200mL;对PCR产物进行基因分型时,总反应体系应不低于40mL。相同DNA模板浓度下,FLUOstar平台可以对抗秆锈病基因显性标记csSr32#1(Sr32)和IB-267(Sr50)的PCR产物进行基因型分型,判断准确率为100%。对特异性强且等位基因片段差异大(≥100bp)的共显性标记,如抗叶锈病基因标记We173(Yr26)等,用荧光染料同样可以进行基因分型。与琼脂糖凝胶电泳相比,荧光染料鉴定等位基因价格略高,但方法简单、准确快速、重现性好,可用于分子育种中世代材料快速筛选。  相似文献   
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基于作物生长模型的冬小麦灌溉方案研究   总被引:1,自引:0,他引:1  
利用作物生长模拟模型(PS123),以黄淮海平原曲周砂壤土种植的冬小麦为例,对2 280个不同淡水灌溉方案和2 055个微咸水灌溉方案进行了模拟研究,分析了不同灌溉方案对作物生产力、水分利用效率的影响。结果表明,曲周地区多年冬小麦平均生产潜力为11.27 t/hm2,冬小麦最高生产潜力的最小需水量为240 mm,与目前节水灌溉试验相吻合;通过灌溉方案模拟,提出了在冬小麦生育期淡水灌溉1到4次,获得高产的最佳灌溉方案;在灌溉4次的冬小麦生产体系中,建议冬前用淡水灌溉,返青后可以考虑1~2次微咸水灌。  相似文献   
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Clinical changes and acute phase responses, including tumour necrosis factor-alpha (tnfalpha), in six buffalo calves were examined following intravenous inoculation of a bolus of endotoxin (1 microg kg(-1) bodyweight in 10 ml of phosphate-buffered saline [ pbs ]) extracted from Pasteurella multocida serotype B:2, the bacterium responsible for haemorrhagic septicaemia (hs) in Asia. Endotoxin injection caused a rapid onset of clinical signs characterised by dullness, sternal recumbency, elevated rectal temperatures, excessive salivation and dyspnoea that lasted for up to 12 hours post-inoculation (p.i.). Serum concentrations of tnfalpha rose within 1 hour p.i. to reach peak values ranging between 8 and 140 ng ml(-1) at 1-2 hours p.i. and then declined rapidly to baseline levels 3-5 hours p.i. Endotoxin injection induced other acute phase changes, including a rapid leucopenia and reductions in the serum concentrations of iron and zinc and a delayed but prolonged increase in haptoglobin from 12 hours p.i. that reached a plateau from about 60 hours p.i. Three control calves injected with 10 ml pbs showed no clinical or blood compositional changes. By reproducing key signs of hs the work confirms a pivotal role of endotoxin in the pathogenesis of hs and emphasises the exquisite sensitivity of the buffalo to P multocida endotoxin.  相似文献   
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为调查新疆和静天山山区牧羊犬细粒棘球绦虫感染现状,从和静县额勒再特乌鲁乡盖干塔克勒根村和额勒再特乌鲁村牧羊犬中随机抽样46只牧羊犬,收集粪便,采用虫卵沉淀法和酶联免疫吸附试验诊断试剂盒进行了细粒棘球绦虫感染情况调查。结果显示两种检查方法的结果完全一致,7只牧羊犬粪样呈阳性,感染率15.2%。其中,盖干塔克勒根村29只牧羊犬中,细粒棘球绦虫阳性犬3只,感染率10.3%;额勒再特乌鲁村17只牧羊犬中,细粒棘球绦虫阳性犬4只,感染率23.5%。该调查结果为制定天山山区人畜细粒棘球蚴病综合防治措施提供了科学依据。  相似文献   
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